1 /* 2 * 3 * Bluetooth HCI Three-wire UART driver 4 * 5 * Copyright (C) 2012 Intel Corporation 6 * 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21 * 22 */ 23 24 #include <linux/acpi.h> 25 #include <linux/errno.h> 26 #include <linux/gpio/consumer.h> 27 #include <linux/kernel.h> 28 #include <linux/mod_devicetable.h> 29 #include <linux/serdev.h> 30 #include <linux/skbuff.h> 31 32 #include <net/bluetooth/bluetooth.h> 33 #include <net/bluetooth/hci_core.h> 34 35 #include "btrtl.h" 36 #include "hci_uart.h" 37 38 #define HCI_3WIRE_ACK_PKT 0 39 #define HCI_3WIRE_LINK_PKT 15 40 41 /* Sliding window size */ 42 #define H5_TX_WIN_MAX 4 43 44 #define H5_ACK_TIMEOUT msecs_to_jiffies(250) 45 #define H5_SYNC_TIMEOUT msecs_to_jiffies(100) 46 47 /* 48 * Maximum Three-wire packet: 49 * 4 byte header + max value for 12-bit length + 2 bytes for CRC 50 */ 51 #define H5_MAX_LEN (4 + 0xfff + 2) 52 53 /* Convenience macros for reading Three-wire header values */ 54 #define H5_HDR_SEQ(hdr) ((hdr)[0] & 0x07) 55 #define H5_HDR_ACK(hdr) (((hdr)[0] >> 3) & 0x07) 56 #define H5_HDR_CRC(hdr) (((hdr)[0] >> 6) & 0x01) 57 #define H5_HDR_RELIABLE(hdr) (((hdr)[0] >> 7) & 0x01) 58 #define H5_HDR_PKT_TYPE(hdr) ((hdr)[1] & 0x0f) 59 #define H5_HDR_LEN(hdr) ((((hdr)[1] >> 4) & 0x0f) + ((hdr)[2] << 4)) 60 61 #define SLIP_DELIMITER 0xc0 62 #define SLIP_ESC 0xdb 63 #define SLIP_ESC_DELIM 0xdc 64 #define SLIP_ESC_ESC 0xdd 65 66 /* H5 state flags */ 67 enum { 68 H5_RX_ESC, /* SLIP escape mode */ 69 H5_TX_ACK_REQ, /* Pending ack to send */ 70 }; 71 72 struct h5 { 73 /* Must be the first member, hci_serdev.c expects this. */ 74 struct hci_uart serdev_hu; 75 76 struct sk_buff_head unack; /* Unack'ed packets queue */ 77 struct sk_buff_head rel; /* Reliable packets queue */ 78 struct sk_buff_head unrel; /* Unreliable packets queue */ 79 80 unsigned long flags; 81 82 struct sk_buff *rx_skb; /* Receive buffer */ 83 size_t rx_pending; /* Expecting more bytes */ 84 u8 rx_ack; /* Last ack number received */ 85 86 int (*rx_func)(struct hci_uart *hu, u8 c); 87 88 struct timer_list timer; /* Retransmission timer */ 89 struct hci_uart *hu; /* Parent HCI UART */ 90 91 u8 tx_seq; /* Next seq number to send */ 92 u8 tx_ack; /* Next ack number to send */ 93 u8 tx_win; /* Sliding window size */ 94 95 enum { 96 H5_UNINITIALIZED, 97 H5_INITIALIZED, 98 H5_ACTIVE, 99 } state; 100 101 enum { 102 H5_AWAKE, 103 H5_SLEEPING, 104 H5_WAKING_UP, 105 } sleep; 106 107 const struct h5_vnd *vnd; 108 const char *id; 109 110 struct gpio_desc *enable_gpio; 111 struct gpio_desc *device_wake_gpio; 112 }; 113 114 struct h5_vnd { 115 int (*setup)(struct h5 *h5); 116 void (*open)(struct h5 *h5); 117 void (*close)(struct h5 *h5); 118 const struct acpi_gpio_mapping *acpi_gpio_map; 119 }; 120 121 static void h5_reset_rx(struct h5 *h5); 122 123 static void h5_link_control(struct hci_uart *hu, const void *data, size_t len) 124 { 125 struct h5 *h5 = hu->priv; 126 struct sk_buff *nskb; 127 128 nskb = alloc_skb(3, GFP_ATOMIC); 129 if (!nskb) 130 return; 131 132 hci_skb_pkt_type(nskb) = HCI_3WIRE_LINK_PKT; 133 134 skb_put_data(nskb, data, len); 135 136 skb_queue_tail(&h5->unrel, nskb); 137 } 138 139 static u8 h5_cfg_field(struct h5 *h5) 140 { 141 /* Sliding window size (first 3 bits) */ 142 return h5->tx_win & 0x07; 143 } 144 145 static void h5_timed_event(struct timer_list *t) 146 { 147 const unsigned char sync_req[] = { 0x01, 0x7e }; 148 unsigned char conf_req[3] = { 0x03, 0xfc }; 149 struct h5 *h5 = from_timer(h5, t, timer); 150 struct hci_uart *hu = h5->hu; 151 struct sk_buff *skb; 152 unsigned long flags; 153 154 BT_DBG("%s", hu->hdev->name); 155 156 if (h5->state == H5_UNINITIALIZED) 157 h5_link_control(hu, sync_req, sizeof(sync_req)); 158 159 if (h5->state == H5_INITIALIZED) { 160 conf_req[2] = h5_cfg_field(h5); 161 h5_link_control(hu, conf_req, sizeof(conf_req)); 162 } 163 164 if (h5->state != H5_ACTIVE) { 165 mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT); 166 goto wakeup; 167 } 168 169 if (h5->sleep != H5_AWAKE) { 170 h5->sleep = H5_SLEEPING; 171 goto wakeup; 172 } 173 174 BT_DBG("hu %p retransmitting %u pkts", hu, h5->unack.qlen); 175 176 spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING); 177 178 while ((skb = __skb_dequeue_tail(&h5->unack)) != NULL) { 179 h5->tx_seq = (h5->tx_seq - 1) & 0x07; 180 skb_queue_head(&h5->rel, skb); 181 } 182 183 spin_unlock_irqrestore(&h5->unack.lock, flags); 184 185 wakeup: 186 hci_uart_tx_wakeup(hu); 187 } 188 189 static void h5_peer_reset(struct hci_uart *hu) 190 { 191 struct h5 *h5 = hu->priv; 192 193 BT_ERR("Peer device has reset"); 194 195 h5->state = H5_UNINITIALIZED; 196 197 del_timer(&h5->timer); 198 199 skb_queue_purge(&h5->rel); 200 skb_queue_purge(&h5->unrel); 201 skb_queue_purge(&h5->unack); 202 203 h5->tx_seq = 0; 204 h5->tx_ack = 0; 205 206 /* Send reset request to upper stack */ 207 hci_reset_dev(hu->hdev); 208 } 209 210 static int h5_open(struct hci_uart *hu) 211 { 212 struct h5 *h5; 213 const unsigned char sync[] = { 0x01, 0x7e }; 214 215 BT_DBG("hu %p", hu); 216 217 if (hu->serdev) { 218 h5 = serdev_device_get_drvdata(hu->serdev); 219 } else { 220 h5 = kzalloc(sizeof(*h5), GFP_KERNEL); 221 if (!h5) 222 return -ENOMEM; 223 } 224 225 hu->priv = h5; 226 h5->hu = hu; 227 228 skb_queue_head_init(&h5->unack); 229 skb_queue_head_init(&h5->rel); 230 skb_queue_head_init(&h5->unrel); 231 232 h5_reset_rx(h5); 233 234 timer_setup(&h5->timer, h5_timed_event, 0); 235 236 h5->tx_win = H5_TX_WIN_MAX; 237 238 if (h5->vnd && h5->vnd->open) 239 h5->vnd->open(h5); 240 241 set_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags); 242 243 /* Send initial sync request */ 244 h5_link_control(hu, sync, sizeof(sync)); 245 mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT); 246 247 return 0; 248 } 249 250 static int h5_close(struct hci_uart *hu) 251 { 252 struct h5 *h5 = hu->priv; 253 254 del_timer_sync(&h5->timer); 255 256 skb_queue_purge(&h5->unack); 257 skb_queue_purge(&h5->rel); 258 skb_queue_purge(&h5->unrel); 259 260 if (h5->vnd && h5->vnd->close) 261 h5->vnd->close(h5); 262 263 if (!hu->serdev) 264 kfree(h5); 265 266 return 0; 267 } 268 269 static int h5_setup(struct hci_uart *hu) 270 { 271 struct h5 *h5 = hu->priv; 272 273 if (h5->vnd && h5->vnd->setup) 274 return h5->vnd->setup(h5); 275 276 return 0; 277 } 278 279 static void h5_pkt_cull(struct h5 *h5) 280 { 281 struct sk_buff *skb, *tmp; 282 unsigned long flags; 283 int i, to_remove; 284 u8 seq; 285 286 spin_lock_irqsave(&h5->unack.lock, flags); 287 288 to_remove = skb_queue_len(&h5->unack); 289 if (to_remove == 0) 290 goto unlock; 291 292 seq = h5->tx_seq; 293 294 while (to_remove > 0) { 295 if (h5->rx_ack == seq) 296 break; 297 298 to_remove--; 299 seq = (seq - 1) & 0x07; 300 } 301 302 if (seq != h5->rx_ack) 303 BT_ERR("Controller acked invalid packet"); 304 305 i = 0; 306 skb_queue_walk_safe(&h5->unack, skb, tmp) { 307 if (i++ >= to_remove) 308 break; 309 310 __skb_unlink(skb, &h5->unack); 311 kfree_skb(skb); 312 } 313 314 if (skb_queue_empty(&h5->unack)) 315 del_timer(&h5->timer); 316 317 unlock: 318 spin_unlock_irqrestore(&h5->unack.lock, flags); 319 } 320 321 static void h5_handle_internal_rx(struct hci_uart *hu) 322 { 323 struct h5 *h5 = hu->priv; 324 const unsigned char sync_req[] = { 0x01, 0x7e }; 325 const unsigned char sync_rsp[] = { 0x02, 0x7d }; 326 unsigned char conf_req[3] = { 0x03, 0xfc }; 327 const unsigned char conf_rsp[] = { 0x04, 0x7b }; 328 const unsigned char wakeup_req[] = { 0x05, 0xfa }; 329 const unsigned char woken_req[] = { 0x06, 0xf9 }; 330 const unsigned char sleep_req[] = { 0x07, 0x78 }; 331 const unsigned char *hdr = h5->rx_skb->data; 332 const unsigned char *data = &h5->rx_skb->data[4]; 333 334 BT_DBG("%s", hu->hdev->name); 335 336 if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) 337 return; 338 339 if (H5_HDR_LEN(hdr) < 2) 340 return; 341 342 conf_req[2] = h5_cfg_field(h5); 343 344 if (memcmp(data, sync_req, 2) == 0) { 345 if (h5->state == H5_ACTIVE) 346 h5_peer_reset(hu); 347 h5_link_control(hu, sync_rsp, 2); 348 } else if (memcmp(data, sync_rsp, 2) == 0) { 349 if (h5->state == H5_ACTIVE) 350 h5_peer_reset(hu); 351 h5->state = H5_INITIALIZED; 352 h5_link_control(hu, conf_req, 3); 353 } else if (memcmp(data, conf_req, 2) == 0) { 354 h5_link_control(hu, conf_rsp, 2); 355 h5_link_control(hu, conf_req, 3); 356 } else if (memcmp(data, conf_rsp, 2) == 0) { 357 if (H5_HDR_LEN(hdr) > 2) 358 h5->tx_win = (data[2] & 0x07); 359 BT_DBG("Three-wire init complete. tx_win %u", h5->tx_win); 360 h5->state = H5_ACTIVE; 361 hci_uart_init_ready(hu); 362 return; 363 } else if (memcmp(data, sleep_req, 2) == 0) { 364 BT_DBG("Peer went to sleep"); 365 h5->sleep = H5_SLEEPING; 366 return; 367 } else if (memcmp(data, woken_req, 2) == 0) { 368 BT_DBG("Peer woke up"); 369 h5->sleep = H5_AWAKE; 370 } else if (memcmp(data, wakeup_req, 2) == 0) { 371 BT_DBG("Peer requested wakeup"); 372 h5_link_control(hu, woken_req, 2); 373 h5->sleep = H5_AWAKE; 374 } else { 375 BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]); 376 return; 377 } 378 379 hci_uart_tx_wakeup(hu); 380 } 381 382 static void h5_complete_rx_pkt(struct hci_uart *hu) 383 { 384 struct h5 *h5 = hu->priv; 385 const unsigned char *hdr = h5->rx_skb->data; 386 387 if (H5_HDR_RELIABLE(hdr)) { 388 h5->tx_ack = (h5->tx_ack + 1) % 8; 389 set_bit(H5_TX_ACK_REQ, &h5->flags); 390 hci_uart_tx_wakeup(hu); 391 } 392 393 h5->rx_ack = H5_HDR_ACK(hdr); 394 395 h5_pkt_cull(h5); 396 397 switch (H5_HDR_PKT_TYPE(hdr)) { 398 case HCI_EVENT_PKT: 399 case HCI_ACLDATA_PKT: 400 case HCI_SCODATA_PKT: 401 hci_skb_pkt_type(h5->rx_skb) = H5_HDR_PKT_TYPE(hdr); 402 403 /* Remove Three-wire header */ 404 skb_pull(h5->rx_skb, 4); 405 406 hci_recv_frame(hu->hdev, h5->rx_skb); 407 h5->rx_skb = NULL; 408 409 break; 410 411 default: 412 h5_handle_internal_rx(hu); 413 break; 414 } 415 416 h5_reset_rx(h5); 417 } 418 419 static int h5_rx_crc(struct hci_uart *hu, unsigned char c) 420 { 421 h5_complete_rx_pkt(hu); 422 423 return 0; 424 } 425 426 static int h5_rx_payload(struct hci_uart *hu, unsigned char c) 427 { 428 struct h5 *h5 = hu->priv; 429 const unsigned char *hdr = h5->rx_skb->data; 430 431 if (H5_HDR_CRC(hdr)) { 432 h5->rx_func = h5_rx_crc; 433 h5->rx_pending = 2; 434 } else { 435 h5_complete_rx_pkt(hu); 436 } 437 438 return 0; 439 } 440 441 static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c) 442 { 443 struct h5 *h5 = hu->priv; 444 const unsigned char *hdr = h5->rx_skb->data; 445 446 BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u", 447 hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr), 448 H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr), 449 H5_HDR_LEN(hdr)); 450 451 if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) { 452 BT_ERR("Invalid header checksum"); 453 h5_reset_rx(h5); 454 return 0; 455 } 456 457 if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) { 458 BT_ERR("Out-of-order packet arrived (%u != %u)", 459 H5_HDR_SEQ(hdr), h5->tx_ack); 460 h5_reset_rx(h5); 461 return 0; 462 } 463 464 if (h5->state != H5_ACTIVE && 465 H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) { 466 BT_ERR("Non-link packet received in non-active state"); 467 h5_reset_rx(h5); 468 return 0; 469 } 470 471 h5->rx_func = h5_rx_payload; 472 h5->rx_pending = H5_HDR_LEN(hdr); 473 474 return 0; 475 } 476 477 static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c) 478 { 479 struct h5 *h5 = hu->priv; 480 481 if (c == SLIP_DELIMITER) 482 return 1; 483 484 h5->rx_func = h5_rx_3wire_hdr; 485 h5->rx_pending = 4; 486 487 h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC); 488 if (!h5->rx_skb) { 489 BT_ERR("Can't allocate mem for new packet"); 490 h5_reset_rx(h5); 491 return -ENOMEM; 492 } 493 494 h5->rx_skb->dev = (void *)hu->hdev; 495 496 return 0; 497 } 498 499 static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c) 500 { 501 struct h5 *h5 = hu->priv; 502 503 if (c == SLIP_DELIMITER) 504 h5->rx_func = h5_rx_pkt_start; 505 506 return 1; 507 } 508 509 static void h5_unslip_one_byte(struct h5 *h5, unsigned char c) 510 { 511 const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC; 512 const u8 *byte = &c; 513 514 if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) { 515 set_bit(H5_RX_ESC, &h5->flags); 516 return; 517 } 518 519 if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) { 520 switch (c) { 521 case SLIP_ESC_DELIM: 522 byte = &delim; 523 break; 524 case SLIP_ESC_ESC: 525 byte = &esc; 526 break; 527 default: 528 BT_ERR("Invalid esc byte 0x%02hhx", c); 529 h5_reset_rx(h5); 530 return; 531 } 532 } 533 534 skb_put_data(h5->rx_skb, byte, 1); 535 h5->rx_pending--; 536 537 BT_DBG("unsliped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending); 538 } 539 540 static void h5_reset_rx(struct h5 *h5) 541 { 542 if (h5->rx_skb) { 543 kfree_skb(h5->rx_skb); 544 h5->rx_skb = NULL; 545 } 546 547 h5->rx_func = h5_rx_delimiter; 548 h5->rx_pending = 0; 549 clear_bit(H5_RX_ESC, &h5->flags); 550 } 551 552 static int h5_recv(struct hci_uart *hu, const void *data, int count) 553 { 554 struct h5 *h5 = hu->priv; 555 const unsigned char *ptr = data; 556 557 BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending, 558 count); 559 560 while (count > 0) { 561 int processed; 562 563 if (h5->rx_pending > 0) { 564 if (*ptr == SLIP_DELIMITER) { 565 BT_ERR("Too short H5 packet"); 566 h5_reset_rx(h5); 567 continue; 568 } 569 570 h5_unslip_one_byte(h5, *ptr); 571 572 ptr++; count--; 573 continue; 574 } 575 576 processed = h5->rx_func(hu, *ptr); 577 if (processed < 0) 578 return processed; 579 580 ptr += processed; 581 count -= processed; 582 } 583 584 return 0; 585 } 586 587 static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb) 588 { 589 struct h5 *h5 = hu->priv; 590 591 if (skb->len > 0xfff) { 592 BT_ERR("Packet too long (%u bytes)", skb->len); 593 kfree_skb(skb); 594 return 0; 595 } 596 597 if (h5->state != H5_ACTIVE) { 598 BT_ERR("Ignoring HCI data in non-active state"); 599 kfree_skb(skb); 600 return 0; 601 } 602 603 switch (hci_skb_pkt_type(skb)) { 604 case HCI_ACLDATA_PKT: 605 case HCI_COMMAND_PKT: 606 skb_queue_tail(&h5->rel, skb); 607 break; 608 609 case HCI_SCODATA_PKT: 610 skb_queue_tail(&h5->unrel, skb); 611 break; 612 613 default: 614 BT_ERR("Unknown packet type %u", hci_skb_pkt_type(skb)); 615 kfree_skb(skb); 616 break; 617 } 618 619 return 0; 620 } 621 622 static void h5_slip_delim(struct sk_buff *skb) 623 { 624 const char delim = SLIP_DELIMITER; 625 626 skb_put_data(skb, &delim, 1); 627 } 628 629 static void h5_slip_one_byte(struct sk_buff *skb, u8 c) 630 { 631 const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM }; 632 const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC }; 633 634 switch (c) { 635 case SLIP_DELIMITER: 636 skb_put_data(skb, &esc_delim, 2); 637 break; 638 case SLIP_ESC: 639 skb_put_data(skb, &esc_esc, 2); 640 break; 641 default: 642 skb_put_data(skb, &c, 1); 643 } 644 } 645 646 static bool valid_packet_type(u8 type) 647 { 648 switch (type) { 649 case HCI_ACLDATA_PKT: 650 case HCI_COMMAND_PKT: 651 case HCI_SCODATA_PKT: 652 case HCI_3WIRE_LINK_PKT: 653 case HCI_3WIRE_ACK_PKT: 654 return true; 655 default: 656 return false; 657 } 658 } 659 660 static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type, 661 const u8 *data, size_t len) 662 { 663 struct h5 *h5 = hu->priv; 664 struct sk_buff *nskb; 665 u8 hdr[4]; 666 int i; 667 668 if (!valid_packet_type(pkt_type)) { 669 BT_ERR("Unknown packet type %u", pkt_type); 670 return NULL; 671 } 672 673 /* 674 * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2 675 * (because bytes 0xc0 and 0xdb are escaped, worst case is when 676 * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0 677 * delimiters at start and end). 678 */ 679 nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC); 680 if (!nskb) 681 return NULL; 682 683 hci_skb_pkt_type(nskb) = pkt_type; 684 685 h5_slip_delim(nskb); 686 687 hdr[0] = h5->tx_ack << 3; 688 clear_bit(H5_TX_ACK_REQ, &h5->flags); 689 690 /* Reliable packet? */ 691 if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) { 692 hdr[0] |= 1 << 7; 693 hdr[0] |= h5->tx_seq; 694 h5->tx_seq = (h5->tx_seq + 1) % 8; 695 } 696 697 hdr[1] = pkt_type | ((len & 0x0f) << 4); 698 hdr[2] = len >> 4; 699 hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff); 700 701 BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u", 702 hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr), 703 H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr), 704 H5_HDR_LEN(hdr)); 705 706 for (i = 0; i < 4; i++) 707 h5_slip_one_byte(nskb, hdr[i]); 708 709 for (i = 0; i < len; i++) 710 h5_slip_one_byte(nskb, data[i]); 711 712 h5_slip_delim(nskb); 713 714 return nskb; 715 } 716 717 static struct sk_buff *h5_dequeue(struct hci_uart *hu) 718 { 719 struct h5 *h5 = hu->priv; 720 unsigned long flags; 721 struct sk_buff *skb, *nskb; 722 723 if (h5->sleep != H5_AWAKE) { 724 const unsigned char wakeup_req[] = { 0x05, 0xfa }; 725 726 if (h5->sleep == H5_WAKING_UP) 727 return NULL; 728 729 h5->sleep = H5_WAKING_UP; 730 BT_DBG("Sending wakeup request"); 731 732 mod_timer(&h5->timer, jiffies + HZ / 100); 733 return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2); 734 } 735 736 skb = skb_dequeue(&h5->unrel); 737 if (skb) { 738 nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb), 739 skb->data, skb->len); 740 if (nskb) { 741 kfree_skb(skb); 742 return nskb; 743 } 744 745 skb_queue_head(&h5->unrel, skb); 746 BT_ERR("Could not dequeue pkt because alloc_skb failed"); 747 } 748 749 spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING); 750 751 if (h5->unack.qlen >= h5->tx_win) 752 goto unlock; 753 754 skb = skb_dequeue(&h5->rel); 755 if (skb) { 756 nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb), 757 skb->data, skb->len); 758 if (nskb) { 759 __skb_queue_tail(&h5->unack, skb); 760 mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT); 761 spin_unlock_irqrestore(&h5->unack.lock, flags); 762 return nskb; 763 } 764 765 skb_queue_head(&h5->rel, skb); 766 BT_ERR("Could not dequeue pkt because alloc_skb failed"); 767 } 768 769 unlock: 770 spin_unlock_irqrestore(&h5->unack.lock, flags); 771 772 if (test_bit(H5_TX_ACK_REQ, &h5->flags)) 773 return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0); 774 775 return NULL; 776 } 777 778 static int h5_flush(struct hci_uart *hu) 779 { 780 BT_DBG("hu %p", hu); 781 return 0; 782 } 783 784 static const struct hci_uart_proto h5p = { 785 .id = HCI_UART_3WIRE, 786 .name = "Three-wire (H5)", 787 .open = h5_open, 788 .close = h5_close, 789 .setup = h5_setup, 790 .recv = h5_recv, 791 .enqueue = h5_enqueue, 792 .dequeue = h5_dequeue, 793 .flush = h5_flush, 794 }; 795 796 static int h5_serdev_probe(struct serdev_device *serdev) 797 { 798 const struct acpi_device_id *match; 799 struct device *dev = &serdev->dev; 800 struct h5 *h5; 801 802 h5 = devm_kzalloc(dev, sizeof(*h5), GFP_KERNEL); 803 if (!h5) 804 return -ENOMEM; 805 806 set_bit(HCI_UART_RESET_ON_INIT, &h5->serdev_hu.flags); 807 808 h5->hu = &h5->serdev_hu; 809 h5->serdev_hu.serdev = serdev; 810 serdev_device_set_drvdata(serdev, h5); 811 812 if (has_acpi_companion(dev)) { 813 match = acpi_match_device(dev->driver->acpi_match_table, dev); 814 if (!match) 815 return -ENODEV; 816 817 h5->vnd = (const struct h5_vnd *)match->driver_data; 818 h5->id = (char *)match->id; 819 820 if (h5->vnd->acpi_gpio_map) 821 devm_acpi_dev_add_driver_gpios(dev, 822 h5->vnd->acpi_gpio_map); 823 } 824 825 h5->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW); 826 if (IS_ERR(h5->enable_gpio)) 827 return PTR_ERR(h5->enable_gpio); 828 829 h5->device_wake_gpio = devm_gpiod_get_optional(dev, "device-wake", 830 GPIOD_OUT_LOW); 831 if (IS_ERR(h5->device_wake_gpio)) 832 return PTR_ERR(h5->device_wake_gpio); 833 834 return hci_uart_register_device(&h5->serdev_hu, &h5p); 835 } 836 837 static void h5_serdev_remove(struct serdev_device *serdev) 838 { 839 struct h5 *h5 = serdev_device_get_drvdata(serdev); 840 841 hci_uart_unregister_device(&h5->serdev_hu); 842 } 843 844 #ifdef CONFIG_BT_HCIUART_RTL 845 static int h5_btrtl_setup(struct h5 *h5) 846 { 847 struct btrtl_device_info *btrtl_dev; 848 struct sk_buff *skb; 849 __le32 baudrate_data; 850 u32 device_baudrate; 851 unsigned int controller_baudrate; 852 bool flow_control; 853 int err; 854 855 btrtl_dev = btrtl_initialize(h5->hu->hdev, h5->id); 856 if (IS_ERR(btrtl_dev)) 857 return PTR_ERR(btrtl_dev); 858 859 err = btrtl_get_uart_settings(h5->hu->hdev, btrtl_dev, 860 &controller_baudrate, &device_baudrate, 861 &flow_control); 862 if (err) 863 goto out_free; 864 865 baudrate_data = cpu_to_le32(device_baudrate); 866 skb = __hci_cmd_sync(h5->hu->hdev, 0xfc17, sizeof(baudrate_data), 867 &baudrate_data, HCI_INIT_TIMEOUT); 868 if (IS_ERR(skb)) { 869 rtl_dev_err(h5->hu->hdev, "set baud rate command failed\n"); 870 err = PTR_ERR(skb); 871 goto out_free; 872 } else { 873 kfree_skb(skb); 874 } 875 /* Give the device some time to set up the new baudrate. */ 876 usleep_range(10000, 20000); 877 878 serdev_device_set_baudrate(h5->hu->serdev, controller_baudrate); 879 serdev_device_set_flow_control(h5->hu->serdev, flow_control); 880 881 err = btrtl_download_firmware(h5->hu->hdev, btrtl_dev); 882 /* Give the device some time before the hci-core sends it a reset */ 883 usleep_range(10000, 20000); 884 885 out_free: 886 btrtl_free(btrtl_dev); 887 888 return err; 889 } 890 891 static void h5_btrtl_open(struct h5 *h5) 892 { 893 /* Devices always start with these fixed parameters */ 894 serdev_device_set_flow_control(h5->hu->serdev, false); 895 serdev_device_set_parity(h5->hu->serdev, SERDEV_PARITY_EVEN); 896 serdev_device_set_baudrate(h5->hu->serdev, 115200); 897 898 /* The controller needs up to 500ms to wakeup */ 899 gpiod_set_value_cansleep(h5->enable_gpio, 1); 900 gpiod_set_value_cansleep(h5->device_wake_gpio, 1); 901 msleep(500); 902 } 903 904 static void h5_btrtl_close(struct h5 *h5) 905 { 906 gpiod_set_value_cansleep(h5->device_wake_gpio, 0); 907 gpiod_set_value_cansleep(h5->enable_gpio, 0); 908 } 909 910 static const struct acpi_gpio_params btrtl_device_wake_gpios = { 0, 0, false }; 911 static const struct acpi_gpio_params btrtl_enable_gpios = { 1, 0, false }; 912 static const struct acpi_gpio_params btrtl_host_wake_gpios = { 2, 0, false }; 913 static const struct acpi_gpio_mapping acpi_btrtl_gpios[] = { 914 { "device-wake-gpios", &btrtl_device_wake_gpios, 1 }, 915 { "enable-gpios", &btrtl_enable_gpios, 1 }, 916 { "host-wake-gpios", &btrtl_host_wake_gpios, 1 }, 917 {}, 918 }; 919 920 static struct h5_vnd rtl_vnd = { 921 .setup = h5_btrtl_setup, 922 .open = h5_btrtl_open, 923 .close = h5_btrtl_close, 924 .acpi_gpio_map = acpi_btrtl_gpios, 925 }; 926 #endif 927 928 #ifdef CONFIG_ACPI 929 static const struct acpi_device_id h5_acpi_match[] = { 930 #ifdef CONFIG_BT_HCIUART_RTL 931 { "OBDA8723", (kernel_ulong_t)&rtl_vnd }, 932 #endif 933 { }, 934 }; 935 MODULE_DEVICE_TABLE(acpi, h5_acpi_match); 936 #endif 937 938 static struct serdev_device_driver h5_serdev_driver = { 939 .probe = h5_serdev_probe, 940 .remove = h5_serdev_remove, 941 .driver = { 942 .name = "hci_uart_h5", 943 .acpi_match_table = ACPI_PTR(h5_acpi_match), 944 }, 945 }; 946 947 int __init h5_init(void) 948 { 949 serdev_device_driver_register(&h5_serdev_driver); 950 return hci_uart_register_proto(&h5p); 951 } 952 953 int __exit h5_deinit(void) 954 { 955 serdev_device_driver_unregister(&h5_serdev_driver); 956 return hci_uart_unregister_proto(&h5p); 957 } 958